No, these are the runners, clones of the parent plant. You should peg these plantlets into the ground still attached to the parent plant. This will encourage it to send roots down, after a couple months a good root system should have astablished, then you can cut it free. A good way of increasing your plants and crop size...

....unless of course, you don't want any extra plants. Then simply cut it off and dispose.

Snorer, don't take more than two runners off any individual plant as you will weaken it and the runners won't be as good either (just snip off any extra ones). In general you should replace/renew your strawberry plants at least every three years using this method, although over time diseases may build up, so occasionally you have to buy anew.

If you fill 3 inch plastic pots with a soil/compost mix you can peg the runners straight into this which makes moving them much easier for both you and the plant.

You may be best to snip off any runners until after your harvest as you will get more/larger strawberries that way. The flip side of this, of course, is that your runners won't be as well developed so you will get a smaller crop from them next year. Depends what you want, really - jam today or jam tomorrow.

A good tip if using the pot method for your plantlets/runners. Is to first peg down the pot either with wire through the drainage holes or by digging the pot into the ground. I can't count the times I've used this method only for the pot to tip over and the contents spill everywhere. The pot needs to be stable for X amount of months for the roots to take.